package org.apache.shardingsphere.infra.util.yaml.representer;

import org.apache.shardingsphere.infra.util.yaml.representer.processor.DefaultYamlTupleProcessor;
import org.apache.shardingsphere.infra.util.yaml.representer.processor.ShardingSphereYamlTupleProcessor;
import org.apache.shardingsphere.infra.util.yaml.representer.processor.ShardingSphereYamlTupleProcessorFactory;
import org.apache.shardingsphere.infra.util.yaml.shortcuts.ShardingSphereYamlShortcutsFactory;
import org.yaml.snakeyaml.DumperOptions;
import org.yaml.snakeyaml.introspector.Property;
import org.yaml.snakeyaml.nodes.Node;
import org.yaml.snakeyaml.nodes.NodeTuple;
import org.yaml.snakeyaml.nodes.Tag;
import org.yaml.snakeyaml.representer.Representer;

import java.util.Collection;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Map.Entry;

/**
 * ShardingSphere YAML representer.
 */
public final class ShardingSphereYamlRepresenter extends Representer {

	public ShardingSphereYamlRepresenter(DumperOptions options) {
		super(options);
		ShardingSphereYamlShortcutsFactory.getAllYamlShortcuts().forEach((key, value) -> addClassTag(value, new Tag(key)));
	}

	@Override
	protected NodeTuple representJavaBeanProperty(final Object javaBean, final Property property, final Object propertyValue, final Tag customTag) {
		NodeTuple nodeTuple = super.representJavaBeanProperty(javaBean, property, propertyValue, customTag);
		for (ShardingSphereYamlTupleProcessor each : ShardingSphereYamlTupleProcessorFactory.getAllInstances()) {
			if (property.getName().equals(each.getTupleName())) {
				return each.process(nodeTuple);
			}
		}
		return new DefaultYamlTupleProcessor().process(nodeTuple);
	}

	@SuppressWarnings({"rawtypes", "unchecked"})
	@Override
	protected Node representMapping(final Tag tag, final Map<?, ?> mapping, final DumperOptions.FlowStyle flowStyle) {
		Map skippedEmptyValuesMapping = new LinkedHashMap<>(mapping.size(), 1);
		for (Entry<?, ?> entry : mapping.entrySet()) {
			if (entry.getValue() instanceof Collection && ((Collection) entry.getValue()).isEmpty()) {
				continue;
			}
			if (entry.getValue() instanceof Map && ((Map) entry.getValue()).isEmpty()) {
				continue;
			}
			skippedEmptyValuesMapping.put(entry.getKey(), entry.getValue());
		}
		return super.representMapping(tag, skippedEmptyValuesMapping, flowStyle);
	}
}
